<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        body{
            background-color:pink;
        }
        div {
            width: 300px;
            height: 200px;
            background-image: radial-gradient(circle, red, red 30%, #fff 20%, #fff 100% );
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>